Scary as f*ck.
You’re relaxing in a park in the sun and then all of a sudden, a GIANT PENIS comes out of nowhere and blows its load all over you.
A sexual health charity has decided that freaking people out with their worst Freudian nightmares is a good way to remind them to protect themselves against Sexually Transmitted Diseases. And given that glitter is the herpes of art supplies, having the Giant Penis dump its load on you in the form of glitter seems appropriate.